In recovery procedure for superblock, we try to write data of valid
superblock into invalid one for recovery, work should be finished here,
but then still we will write the valid one with its original data.
This operation is not needed. Let's skip doing this unnecessary work.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

For the first mount of f2fs image with realtime discard option, we will
disable discard option if device is not supported, but for remount
operation, our discard option can still be set, this should be avoided.

This patch moves configuring of discard option to parse_options() to fix
this issue.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Current f2fs check the whether the blk device can support discard.
However, the code will cause the discard option cannot be enabled.
Because the clear_opt(sbi, DISCARD) will be invoked forever.

This patch can fix this issue.

Jaegeuk Kim:
 The original patch was intended to disable the discard option when device
 does not support trim command.
 Rather than remaining the buggy patch, let's replace with this patch as
 an integrated one.

Signed-off-by: Chenxi Mao <chenxi.mao2013@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch applies the following ext4 patch:

  ext4 crypto: use per-inode tfm structure

As suggested by Herbert Xu, we shouldn't allocate a new tfm each time
we read or write a page.  Instead we can use a single tfm hanging off
the inode's crypt_info structure for all of our encryption needs for
that inode, since the tfm can be used by multiple crypto requests in
parallel.

Also use cmpxchg() to avoid races that could result in crypt_info
structure getting doubly allocated or doubly freed.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch recovers a broken superblock with the other valid one.

Signed-off-by: hujianyang <hujianyang@huawei.com>
[Jaegeuk Kim: reinitialize local variables in f2fs_fill_super for retrial]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch splits f2fs_crypto_init/exit with two parts: base initialization and
memory allocation.

Firstly, f2fs module declares the base encryption memory pointers.
Then, allocating internal memories is done at the first encrypted inode access.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

As Hu reported, F2FS has a space leak problem, when conducting:

1) format a 4GB f2fs partition
2) dd a 3G file,
3) unlink it.

So, when doing f2fs_drop_inode(), we need to truncate data blocks
before skipping it.
We can also drop unused caches assigned to each inode.

Reported-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

I use f2fs filesystem with /data partition on my Android phone
by the default mount options. When I remount /data in order to
adding discard option to run some benchmarks, I find the default
options such as background_gc, user_xattr and acl turned off.

So I introduce a function named default_options in super.c. It do
some default setting, and both mount and remount operations will
call this function to complete default setting.

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Most of parts were copied from ext4, except:

 - add f2fs_restore_and_release_control_page which returns control page and
   restore control page
 - remove ext4_encrypted_zeroout()
 - remove sbi->s_file_encryption_mode & sbi->s_dir_encryption_mode
 - add f2fs_end_io_crypto_work for mpage_end_io

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds f2fs_sb_info and page pointers in f2fs_io_info structure.
With this change, we can reduce a lot of parameters for IO functions.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>